What is Your Favorite Multi-Person Video Chat Client?

This semester, I’m teaching an online graduate seminar on the digital humanities (see the course syllabus here!), and I’m requiring that my students meet with me once a week on video chat for a traditional seminar-style discussion. I generally use Google Hangouts and Skype Premium for free or inexpensive videoconferencing, but have been annoyed with the bugginess of both applications.

Wondering what else was out there, I turned to my social media hive mind to ask what other software people were ...